At the beginning of 1927, Great Britain, fearing losing position in China as a result of the Chinese revolution of 1925-1927, demanded from the USSR to stop the military and political support of the amalgamated Kuomintang-Communist government.
The USSR's refusal to comply with the terms of the "Chamberlain's Note" led to a sharp deterioration in relations between Britain and the USSR. The Chinese raid on the Soviet Embassy in Beijing (6th of April) and a search conducted by the British police in the Soviet-English Arcos joint-stock company in London (12th of May) excavated some of secret Soviet documents to the conservative government of Stanley Bolduin which confirmed the "subversive activities" of the Moscow Comintern in the United Kingdom and China.
Thereafter Britain severed trade and diplomatic relations with the USSR (27th of May). In the Soviet Union, this was perceived as the preparation of a "crusade" against the USSR, which led to an increase in military funding, fueled by the intensification of the struggle with White Guard emigration both inside the country (the terrorist attacks in Moscow, Leningrad, Minsk) and abroad (Voikov's murder in Warsaw).
In the late twenties and early thirties, Soviet theorists believed that the formation of a "small Eastern European Entente" in the form of Poland, Romania and the Baltic states alliance was most likely, which would result in the invasion of Soviet Belarus and Soviet Ukraine with financial and material support from Britain and France.